Battery devices

ABSTRACT

A battery carrier configured to be mounted to a tool body of an electric tool for supplying electric power to the tool body is provided. The battery carrier may include a plurality of battery mount sections disposed at a first surface of the battery carrier and each configured to hold a battery, a tool body mount section disposed at a second surface of the battery carrier opposite to the first surface and configured to be mounted to the tool body, and a marker disposed at the first surface and serving as a target for movement of the tool body mount section relative to the tool body when the tool body mount section is mounted to the tool body.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of pending U.S. patent applicationSer. No. 13/495,246 filed Jun. 13, 2012, and which claims priority toJapanese Application No. 2011-132170, filed Jun. 14, 2011, JapaneseApplication No. 2011-132162, filed Jun. 14, 2011, Japanese ApplicationNo. 2011-132168, filed Jun. 14, 2011, and Japanese Application No.2011-132171, filed Jun. 14, 2011, the disclosures of which are expresslyincorporated herein by reference in their entireties.

This application claims priority to Japanese patent application serialnumbers 2011-132162, 2011-132168, 2011-132170 and 2011-132171, thecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

Embodiments of the present invention relate to battery devices. They aretypically adapted to be mounted to the body of an electric tool. Theymay have a plurality of battery packs (also known as batteries) thatserve as a power source in an electric tool.

Description of the Related Art

In recent years, there have been cordless electric tools that include atool body to which a rechargeable battery pack (also known as arechargeable battery) is mounted for serving as a power source.Rechargeable battery packs used for this purpose have been standardizedso as to be commonly used as power sources for different kinds ofelectric tools. Therefore, many users retain a plurality of standardizedrechargeable battery packs. Generally used standardized rechargeablebattery packs have a rating voltage of 18 V for providing a power supplyvoltage of 18 V.

On the other hand, there are some electric tools, such as lawn mowersand chain saws, operating with a supply of 36 V. For these electrictools, the typical 18 V battery packs cannot be used. Therefore, inorder to enable the 18 V battery packs to be used for these electrictools, DE102008040061A1 (also published as US2011/0147031A1) hasproposed a battery device for converting a power supply with a voltageof 18 V into a power supply voltage with 36 V. The battery device ofthis publication is configured to enable two battery packs to be used asa power source. With this battery device, the 18 V battery packs can beused in place of a 36 V battery pack, so that it is possible to handlethe two 18 V battery packs as if they are a 36 V battery pack.Therefore, the use of standardized battery packs can be employed inproducts that they were not originally created for.

However, the battery device disclosed in the above publication still hasa problem whereby the increased size of the battery device caused byoverlapping battery packs leads to difficulty in handling the electrictool.

Therefore, there has been a need in the art for a battery device that isimproved in its handling property.

SUMMARY OF THE INVENTION

In one aspect according to the present teachings, a battery device canbe mounted to a tool body of an electric tool for supplying electricpower to the tool body. The battery device may include a plurality ofbattery mount sections each capable of mounting a battery pack. Theplurality of battery mount sections may be arranged in a juxtaposedrelationship with each other on one side of the battery device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an electric lawn mower having a battery devicemounted thereto;

FIG. 2 is a perspective view of the battery device showing the statewhere battery packs have been removed from the battery device;

FIG. 3 is a side view of the battery device having the battery packsmounted thereto;

FIG. 4 is a plan view of the battery device having the battery packsmounted thereto;

FIG. 5 is a rear view of the battery device having the battery packsmounted thereto;

FIG. 6 is a bottom view of the battery device having the battery packsmounted thereto;

FIG. 7 is a sectional view taken along line VII-VII in FIG. 6;

FIG. 8 is a plan view of a battery device;

FIG. 9 is a rear view of the battery device shown in FIG. 8; and

FIG. 10 is a rear view with a part shown in cross section of a batterydevice.

DETAILED DESCRIPTION OF THE INVENTION

Each of the additional features and teachings disclosed above and belowmay be utilized separately or in conjunction with other features andteachings to provide improved battery devices. Representative examplesof the present invention, which examples utilize many of theseadditional features and teachings both separately and in conjunctionwith one another, will now be described in detail with reference to theattached drawings. This detailed description is merely intended to teacha person of skill in the art further details for practicing preferredaspects of the present teachings and is not intended to limit the scopeof the invention. Only the claims define the scope of the claimedinvention. Therefore, combinations of features and steps disclosed inthe following detailed description may not be necessary to practice theinvention in the broadest sense, and are instead taught merely toparticularly describe representative examples of the invention.Moreover, various features of the representative examples and thedependent claims may be combined in ways that are not specificallyenumerated in order to provide additional useful examples of the presentteachings. Various examples will now be described with reference to thedrawings.

In one example, a battery device can be mounted to a tool body of anelectric tool for supplying electric power to the tool body. The batterydevice may include a plurality of battery mount sections arranged in ajuxtaposed relationship with each other and each capable of holding abattery pack that has a length along a longitudinal direction. Thebattery mount sections may be arranged and configured so that thelongitudinal directions of the battery packs mounted to the batterymount sections extend substantially parallel to each other with thebattery packs aligned with each other on their longitudinal axes.

Therefore, the length of a group of the battery packs can be minimized,and it is also possible to minimize the thickness of a group of thebattery packs. As a result, it is possible to reduce the length and thethickness of the entire battery device with the mounted battery packs.

In addition, when a battery device has a control circuit board, thecontrol circuit board may be positioned to extend in a directionintersecting the longitudinal directions of the battery packs, so thatit is possible to minimize the size of the battery device in a directionalong the longitudinal directions of the battery packs.

The battery mount sections may be configured such that the battery packis mounted by sliding the battery pack into the battery mount section ina longitudinal direction.

The battery packs may be provided with slide mechanisms or guide railsalong their longitudinal lengths for aiding their smooth attachment tothe battery mount sections.

Each of the battery mounting devices may have a thickness that issmaller than a thickness of each of the battery packs mounted to thebattery mount sections.

With this arrangement, it is possible to reduce the vertical height ofthe battery device. Therefore, the size of the battery device can beminimized.

When the battery packs are mounted to the battery mount sections, aspace may exist near the battery mount sections for enabling a user tograsp the battery packs when removing the battery packs from the batterymount sections.

With this arrangement, the user can insert his or her fingers into thespace for grasping the battery packs. Therefore, mounting to andremoving the battery packs from the battery device can be easilyperformed.

The space may be set to have a distance of about 10 to 20 mm. With thisdistance, the user can easily enter his or her fingers into the spacewithout having to substantially increase the size of the battery device.The distance of about 10 to 20 mm is determined based on an intermediatevalue of 15 mm. 15 mm is slightly larger than the average thickness ofan adult user.

A part of an outer surface of the enclosure portion and a part of anouter surface of one of the battery packs mounted to the battery mountsections may be substantially positioned within the same plane.

With this arrangement, the battery device may be placed on a surfacewith a part of the outer surface of the enclosure portion and a part ofthe outer surface of the battery pack(s) both contacting the surface.

In another example, a battery device can be mounted to a tool body of anelectric tool for supplying electric power to the tool body. The batterydevice may include a plurality of battery mount sections arranged in ajuxtaposed relationship along an arrangement plane, each capable ofholding a battery pack. The battery device may also include an enclosureportion extending on a battery mounting side of the battery device alonga direction intersecting with the arrangement plane of the battery mountsections.

With this arrangement, the space occupied by the enclosure portion canbe appropriately based depending on the configuration and the size ofthe battery packs. Therefore, the configuration and the size of thebattery device can be minimized to correspond to the size and theconfiguration of the battery packs.

The battery mount sections and the enclosure portion may be arranged inan L-shape as viewed from a lateral side of the enclosure portion. Acontrol circuit board may be positioned within the enclosure portion.

With this arrangement, the battery device may have a configurationwhereby it surrounds the battery packs from two different sides (i.e.,two different directions). Further, because the control circuit boardmay be disposed within the enclosure portion, the battery mount sectionscan be configured to function exclusively for holding the battery packs.Therefore, the size of the battery device with the battery packs mountedthereto can be minimized. It is also possible to reduce the volume ofthe battery mount sections, and thus the battery device.

In another example, a battery device capable of being mounted to a toolbody of an electric tool may include a mount section having a slidemechanism. The battery device can use this slide mechanism when beingattached to the tool body. The mount section may include an engagingmechanism for engaging the tool body when the battery device is in themount position. The engaging mechanism may include an operation portionused for releasing engagement of the tool body. The operation portionmay include a pushing force receiving surface that can be pushed foroperating the operation member. The pushing force receiving surface mayextend substantially in the mounting direction.

With this arrangement, the engaging mechanism can hold the batterydevice at the mount position with respect to the tool body after thebattery device has been moved to the mount position. In addition,because the pushing force receiving surface may extend substantially inthe mounting direction, the size of the battery device in the directionperpendicular to the mounting direction can be minimized even when itincludes the operation portion of the engaging mechanism. Therefore, thesize of the battery device can be minimized even with the engagingmechanism for holding the battery device at the mount position.

The engaging mechanism may include a male hook portion and a female hookportion provided on the tool body. The male hook portion may engage thefemale hook portion when the battery device is positioned at the mountposition. The male hook portion may protrude in a protruding direction.The pushing force receiving surface preferably extends substantiallyperpendicular to the protruding direction of the male hook portion.

For example, pushing the pushing force receiving surface may move themale hook portion in a direction opposite the protruding direction, sothat the male hook portion may be disengaged from the female hookportion of the tool body. Because the pushing force receiving surfaceextends substantially perpendicular to the protruding direction of themale hook portion, the pushing force may be applied in the samedirection as the moving direction of the male hook portion. Therefore,the operation for releasing engagement of the male hook portion can beeasily and efficiently performed.

The pushing force receiving surface may have a length in the mountingdirection of the battery device and may have a width in a directionperpendicular to the mounting direction. The length may be set to belonger than the width. This may facilitate the pushing operation of thepushing force receiving surface for releasing engagement of the malehook portion.

In another example, a battery device capable of being mounted to a toolbody of an electric tool may include a first mount section and a secondmount section. The first mount section is configured to hold a pluralityof battery packs. The second mount section may be configured to bemounted to the tool body and disposed on a first side of the batterydevice. A marker may be disposed on a second side opposite the firstside and may serve as a target for movement of the second mount sectionrelative to the tool body when the second mount section is mounted tothe tool body.

With this arrangement, the user can smoothly perform the operation formounting the second mount section to the tool body as he or she viewsthe marker. Therefore, the operation for mounting the battery device tothe tool body can be easily performed without having to look at a regionbetween the battery device and the tool body.

The mount section may include a slide mechanism, so that the mountsection can be slid relative to the tool body in a mounting direction.The marker may include a marker line. The battery device can be mountedto the tool body by moving the battery device toward the marker line ina direction of the marker line.

The marker line may include a first line and a second line spaced fromeach other by a distance corresponding to a width of one battery pack.In such a case, the tool body may also have markers spaced from eachother by a distance corresponding to a width of one battery pack.Therefore, the markers of the tool body may be used when mounting thebattery device to the tool body and may be also used when a singlebattery pack is directly mounted to the tool body.

Embodiments will now be described with reference to FIGS. 1 to 7. FIG. 1shows a lawn mower 1 incorporating a battery device 10. The lawn mower 1is an example of an electric tool and may be used as a gardening toolfor mowing lawn grasses. The lawn mower 1 is configured as a cordlesstool and is driven with a supply of an electric power from rechargeablebattery packs as will be explained later. Thus, the battery device 10may be mounted to a mower body 2 (i.e., a tool body), so that the mowerbody 2 can be operated with a supply of an electric power from thebattery device 10. More specifically, an electric motor (not shown) maybe mounted within the mower body 2, so that the electric motor canrotate with the supply of an electric power to rotatably drive a cuttingblade (not shown) for mowing lawn grasses. The cutting blade may be alsomounted within the mower body 2. The lawn mower 1 preferably has fourwheels 3 that they are mounted to the mower body 2 and preferablyinclude a pair of front wheels 3 and a pair of rear wheels 3. The wheels3 in each pair may be positioned on opposite sides in the left and rightdirections. As noted above, the battery device 10 serves as a powersource for supplying an electric power to the mower body 2. In thisexample, the lawn mower 1 is configured to operate with a supply of anelectric power of 36 V during the use.

Embodiments of the battery device 10 will now be described. FIG. 2 showsa perspective view of the battery device 10 in the state where batterypacks 90 have been removed from the battery device 10. FIGS. 3, 4, 5, 6and 7 show a side view, a plan view, a rear view, a bottom view and asectional view taken along line VII-VII in FIG. 6, respectively, of thebattery device 10 having the battery packs 90 mounted thereto. For thepurpose of explanation, the following description will be made with adetermination that (a) the side in a mounting direction of the batterypack 90, along which the battery pack 90 is slid for mounting to themower body 2 (tool body), is a front side and (b) the side of thebattery packs 90 (mounted state) with respect to the battery device 10is an upper side.

As shown in FIG. 4, the battery device 10 may be configured to be ableto hold two battery packs 90 each having a rating voltage of 18 V andserving as a power source for the mower body 2. The two battery packs 90may be electrically connected in series to supply a power source voltageof 36 V to the mower body 2. To this end, the battery device 10 mayinclude two battery mount sections 20 each configured to be able to holdone battery pack 90. The battery mount sections 20 are preferablydisposed on the upper surface side of the battery device 10 and arearranged in a juxtaposed relationship. In addition, as shown in FIG. 6,the battery device 10 preferably has a single mount section 40 disposedon the lower surface side of the battery device 10 for mounting to acorresponding mount section 5 of the mower body 2. The battery device 10preferably has a case 11 having an enclosure portion 60, in which a maincontrol circuit board 62 is disposed (see FIG. 7). Therefore, thebattery device 10 is generally composed of the case 11 having theenclosure portion 60 and the battery mount sections 20 and the mountsection 40 disposed on the case 11.

The case 11 may be formed by a molding process using plastic orsynthetic resin and may include a case body 111 and a lid 112 that arejoined to each other. As shown in FIGS. 2 and 3, the case 11 preferablyhas a substantially L-shape as viewed from the lateral side and define ahollow internal space that extends in the lateral directions (the rightand left directions). Various electric wires and various control circuitboards including the main control circuit board 62 may be disposedwithin the hollow internal space.

As shown in FIGS. 2 and 3, the battery mount sections 20 may be providedon the case 11 to extend from the rear end of the case 11 to a middleposition of the case 11 with respect to the forward and rearwarddirections and may be disposed to be juxtaposed in the left and rightdirections. The enclosure portion 60 may be formed at the front end ofthe case 11 and extend in the left and right directions. Morespecifically, a portion of the case 11 where the battery mount sections20 are provided is configured to have a hollow structure having arelatively small height and extending both in the forward and rearwarddirections and the left and right directions. The battery packs 90 maybe positioned on the upper side of the battery mount sections 20 whenthey are moved to mount positions with respect to the respective batterymount sections 20. The enclosure portion 60 is preferably a hollowstructure portion formed at the rear end of the case 11. It preferablyhas a height larger than that of the portion having the battery mountsections 20, so that the enclosure portion 60 extends upward beyond theportion having the battery mount sections 20. Therefore, the enclosureportion 60 extends upward past the battery mount sections 20 in adirection that intersects with a direction of a plane along which thebattery mount sections 20 are juxtaposed with each other. As will bedescribed later, the mount section 40 may be disposed on the case 11 onthe side opposite where the battery mount sections 20 are disposed.

The battery packs 90 are preferably mounted to the battery mountsections 20 at positions on the upper side thereof. When the batterypacks 90 are mounted to the mount position with respect to the batterymount sections 20, an upper end surface 601 of the enclosure portion 60may be positioned at substantially the same level as upper surfaces 901of the battery packs 90. Thus, the height of the enclosure portion 60may be determined according to the height of the battery packs 90 thatare mounted to the battery mount sections 20. In this way, the enclosureportion 60 may be configured to extend upward from the remaining portionof the case 11 and to extend along substantially the entire width of thebattery device 10 in the left and right directions. Therefore, as shownin FIG. 3, the positional relationship between the battery mountsections 20 and the enclosure portion 60 can be determined such thatthey form a substantially L-shape as viewed from a side view, i.e. inthe left and right extending direction of the enclosure portion 60. Inother words, the battery device 10 may be configured to have the batterymount sections 20 and an enclosure portion 60 that are integrated witheach other to form an L-shape (i.e., a structure having two componentsextending in different directions). Further, the thickness of thebattery mount sections 20 in the vertical direction is preferably set tobe smaller than the thickness of the battery packs 90 mounted to thebattery mount sections 20.

Referring to FIG. 7, the main control circuit board 62 disposed withinthe enclosure portion 60 may be electrically connected to the batterypacks 90 that are mounted to the battery mount sections 20. The maincontrol circuit board 62 may serve to receive the supply of the electricpower from the battery packs 90 and to output the electric power to themower body 2 after transforming the supplied voltage.

The battery mount sections 20 will now be described. As describedpreviously, the battery mount sections 20 are preferably disposed at thecase 11 in a juxtaposed relationship with each other. More specifically,the battery mount sections 20 are preferably configured to be able tohold the corresponding battery packs 90 as the battery packs 90 are slidonto the battery mount sections 20. The longitudinal axes of the batterypacks 90 and the battery mount sections 20 oriented such that theirsliding directions are parallel to each other. In other words, thebattery mount sections 20 are arranged in parallel to each other andalso parallel to the sliding directions or the mounting directions ofthe battery packs 90 (i.e., the longitudinal axes of the battery packs90 in the mounted state). In addition, in this example, the lengths ofthe battery packs 90 along their longitudinal directions are the samewith each other. Therefore, in the mounted state, the longitudinal axesof the battery packs 90 extend parallel to each other, and opposite endsin the longitudinal direction of each of the battery packs 90 arepositioned to be aligned with opposite ends in the longitudinaldirection of the other battery pack 90. In certain embodiments, the endsof parallel-aligned battery mount sections 20 as well as battery packs90 may not lie in the same lateral locations. In other embodiments,their starting and/or stopping points may exist in the same relativelateral locations.

Because the battery mount sections 20 may be the same in construction,the construction of only one of the battery mount sections 20 will bedescribed. The battery mount section 20 may be configured such that thebattery pack 90 can be slidably mounted to the battery mount section 20and can be electrically connected to the battery mount section 20. Morespecifically, the battery mount section 20 may have a slide mechanism 21and an electrical connector mechanism 31. The slide mechanism 21 ispreferably configured to be able to slidably engage the battery pack 90and preferably includes a pair of guide rails 23 for slidably engaging acorresponding pair of male guide portions provided on the battery pack90. The guide rails 23 are preferably disposed on the left side and theright side of the battery mount section 20, respectively, and extend inthe forward and rearward directions. The guide rails 23 are preferablyconfigured to have female guide portions corresponding to the male guideportions of the battery pack 90. Therefore, the battery pack 90 can beslid in a direction from the rear side toward the front side under theguide of the guide rails 23 until reaching the mount position.

In this way, the slide mechanism 21 serves to guide the battery pack 90for sliding movement from the rear side toward the front side to enablethe battery pack 90 to be mounted to the battery mount section 20. Theelectrical connector mechanism 31 serves to electrically connect thebattery pack 90 to the battery mount section 20 when the battery pack 90has reached the mount position. More specifically, the electricalconnector mechanism 31 includes a positive terminal 33, a negativeterminal 35 and a control terminal 37. The positive terminal 33 may havea male connecting portion for connecting with a corresponding femaleconnecting portion of a positive terminal (not shown) of the batterypack 90. Similarly, the negative terminal 35 may have a male connectingportion for connecting with a corresponding female connecting portion ofa negative terminal (not shown) of the battery pack 90. The controlterminal 37 may have a male connecting portion for connecting with acorresponding female connecting portion of a control terminal (notshown) of the battery pack 90. In this way, when the battery pack 90 hasreached the mount position, the positive terminal 33, the negativeterminal 35 and the control terminal 37 of the electric connectormechanism 31 are electrically connected to the positive terminal, thenegative terminal and the control terminal of the battery pack 90,respectively.

As shown in FIG. 2, the battery mount section 20 may be configured toprovide a finger insertion space with a spacing distance S1 between thefront end of the battery pack 90 and the rear surface of the enclosureportion 60 when the battery pack 90 has been mounted to the batterymount section 20. The finger insertion space S1 allows the user toinsert his or her fingers when the user intends to remove the batterypack 90 from the battery mount section 20. For example, the spacingdistance S1 may be set to be 10 mm to 20 mm. Preferably, taking intoaccount of the thickness of fingers of an average user, the spacingdistance S1 may be set to be about 15 mm measured at an intermediateposition with respect to the vertical direction of the finger insertionspace. The finger insertion space positioned on the front side of thebattery pack 90 enables the user to push the battery pack 90 in theremoving direction, so that the removal of the battery pack 90 can beeasily performed. In addition, the finger insertion space is positionedon the side opposite to an operation portion 95 of the battery pack 90,which is used for releasing the engagement of the battery pack 90 andthe battery mount section 20. Therefore, this arrangement isadvantageous in that the user can easily perform the operation forreleasing engagement of the battery pack 90.

The mount section 40 will now be described. The mount section 40 isconfigured such that the battery device 10 can be slidably mounted tothe mount section 5 of the mower body 2 (see FIG. 1) and can beelectrically connected to the mount section 5. The mount section 40 ispreferably disposed on the backside of the battery device 10 andincludes a mount structure 41 and an engaging structure 51. The mountstructure 41 preferably includes a slide mechanism and an electricalconnector mechanism. The engaging structure 51 is preferably configuredto be able to engage the mount structure 41 with the mount section 5 andto disengage the mount structure 41 from the mount section 5. The slidemechanism of the mount structure 41 preferably includes a pair of maleguide portions 42 for slidably engaging a pair of guide rails (notshown) provided on the mount section 5. The male guide portions 42 arepreferably disposed on the left side and the right side of the mountsection 40 and extend in the forward and rearward directions. Theelectrical connector mechanism of the mount structure 41 may serve toelectrically connect the mount section 40 to the mount section 5 whenthe battery device 10 has reached the mount position. More specifically,the electrical connector mechanism preferably includes a positiveterminal 43, a negative terminal 45 and a control terminal 47. Thepositive terminal 43 may have a female connecting portion for connectingwith a corresponding male connecting portion of a positive terminal (notshown) of the mount section 5. Similarly, the negative terminal 45 mayhave a female connecting portion for connecting with a correspondingmale connecting portion of a negative terminal (not shown) of the mountsection 5, and the control terminal 47 may have a female connectingportion for connecting with a corresponding male connecting portion of acontrol terminal (not shown) of the mount section 5.

The engaging structure 51 of the mount structure 41 is preferablyconfigured as a male hook mechanism that is capable of being engagedwith and disengaged from the mount section 5. More specifically, asshown in FIG. 7, the engaging structure 51 preferably includes a malehook member 52 and a spring 59 for biasing the male hook member 52.

The male hook member 52 preferably is adjustably (preferably in thevertical direction) supported by the case 11 and is normally biased bythe spring 59 in the downward direction toward the outside of the case11. The male hook member 52 preferably includes a male hook portion 53and an operation portion 55 formed integrally with each other. Theoperation portion 55 may be used for releasing engagement of the malehook portion 55. A guide hole 57 may be formed in the male hook member52 at a position between the male hook portion 53 and the operationportion 55. The male hook portion 53 may be positioned at the outer end(lower end) of the male hook member 52 and may be engageable with afemale hook portion (not shown) of the mount section 5 of the mower body2. The male hook portion 53 preferably has a stopper surface 531 and aninclined surface 532. The stopper surface 531 is preferably configuredto contact a surface of the female hook portion of the mount section 5during engagement of the male hook portion 53 with the female hookportion. The inclined surface 532 preferably serves to facilitatemovement of the male hook portion 53 for engaging with the female hookportion. The operation portion 55 is preferably disposed at the rearportion of the male hook member 52 and extends rearward from the malehook portion 53 in a direction intersecting with the protrudingdirection (vertical direction in this example) of the male hook portion53 so as to be exposed to the outside. Thus, the operation portion 55can be operated by the user for releasing engagement of the male hookportion 53 with the female hook portion of the mount section 5 of themower body 2. The operation portion 55 is preferably configured to havea concave shape with a central bottom surface that serves as a pushingforce receiving surface 56 (see FIGS. 6 and 7). Therefore, the user canpush the pushing force receiving surface 56 for operating the operationportion 55.

As described above, pushing the pushing force receiving surface 56 canrelease the engagement of the male hook portion 53 with the female hookportion of the mount section 5 of the mower body 2. The pushing forcereceiving surface 56 is preferably configured as a flat surface thatextends in a different direction from a pushing force receiving surface96 of the operation portion 95 of the battery pack 90. Thus, the pushingforce receiving surface 56 extends within a plane along the slidingdirection or the mounting direction (forward and rearward direction inthis example) of the battery device 10 for mounting to the mount section5 of the mower body 2. In addition, the plane of the pushing forcereceiving surface 56 is preferably perpendicular to the protrudingdirection (vertical direction in this example) of the male hook portion53. In other words, the plane of the pushing force receiving surface 56is preferably perpendicular to the moving direction of the male hookmember 52. Incidentally, if the battery device 10 is positioned toextend in the horizontal direction, the sliding directions of thebattery packs 90 for mounting to the corresponding battery mountsections 20 may also extend in the horizontal direction. In such a case,the plane of the pushing force receiving surface 45 also extends in thehorizontal direction, i.e., the direction parallel to the slidingdirections of the battery packs 90. In this example, the pushing forcereceiving surface 56 has a rectangular shape. More specifically, thelength of the pushing force receiving surface 56 in the forward andreward directions (i.e., the sliding directions of the battery packs 90or the sliding direction of the battery device 19) is set to be longerthan the width in the left and right direction (i.e., the directionperpendicular to the sliding directions of the battery packs 90 or thesliding direction of the battery device 19). On the other hand, thepushing force receiving surface 96 of the operation portion 95 of thebattery pack 90 may be inclined relative to the sliding direction of thebattery device 10 for mounting to the mount section 5, and therefore,the pushing force receiving surface 96 may be inclined relative to thehorizontal direction when the battery device 10 is positioned to extendin the horizontal direction.

The direction of movement of the operation portion 55 for releasing theengagement of the male hook portion 53 with the female hook portion ofthe mount section 5 of the mower body 2 may be set to be upward withrespect to the battery device 10 or toward inside of the case 11. Thus,if the user pushes the operation portion 55 upward against the biasingforce of the biasing spring 59, the male hook portion 53 retracts intothe battery device 10, so that the male hook portion 53 can bedisengaged from the female hook portion provided on the mount section 5of the mower body 2. The guide hole 57 serves to guide the protrudingand retracting movements of the male hook portion 53, and for thispurpose, the guide hole 57 is preferably formed at a position betweenthe male hook portion 53 and the operation portion 55. It preferablyslidably receives a cylindrical guide member 58 that is integrated withthe case 11 and protrudes from inside of the case 11. The guide hole 57may be opened in the vertical direction and the cylindrical guide member58 may also extend in the vertical direction. Therefore, as theoperation portion 55 is pushed upward against the biasing force of thespring 59, the male hook portion 53 may retract into the case 11 underthe guide of the cylindrical guide member 58. In this example, thespring 59 is a compression coil spring having one end contacting withthe case 11 and the other end contacting with a portion of the male hookmember 52 around the guide hole 57, so that the male hook member 52 isbiased downward toward the outside of the case 11.

As shown in FIGS. 1 and 2, a marker 65 is preferably provided on theupper surface of the enclosure portion 60 of the battery device 10, sothat the mount section 40 can be mounted to the mower body 2 by usingthe marker 65 as a target for movement. Therefore, the battery device 10can be easily mounted to the battery device 10 by moving the batterydevice 10 to slide toward the marker 65. To this end, the marker 65 ispositioned on the upper side opposite the lower side (backside) wherethe mount section 40 is positioned. In addition, the marker 65 ispreferably provided on the upper surface of the enclosure portion 60which is positioned at the front end of the battery device 10 withrespect to the mounting direction of the battery device 10. As shown inFIGS. 2 and 4, the marker 65 may be raised upward from the upper surfaceof the enclosure portion by a given distance and is preferablypositioned to correspond to markers 5 a and 5 b that are provided on theupper surface of the mower body 2. More specifically, the marker 65preferably includes opposite end edges 651 and 652 that are aligned withthe markers 5 a and 5 b, respectively, when the battery device 10 islocated at the mount position with respect to the mount section 5 underthe guide of the slide mechanism 21. Therefore, the end edges 651 and652 of the marker 65 may serve as marker lines. The distance between theend edges 651 and 652 is set to correspond to the width of one batterypack 90 or one battery pack having a rating voltage of 36 V. In thisway, the end edges 651 and 652 may be aligned with the markers 5 a and 5b, respectively, in the mounting direction of the battery device 10.Therefore, in order to mount the battery device 10 to the mount section5 of the mower body 2, the user may position the battery device 10 suchthat the end edges 651 and 652 are aligned with the markers 5 a and 5 bof the mower body 2, respectively. The battery device 10 may then beslid forward under the guide of the slide mechanism 21, so that thebattery device 10 can be mounted to the mount section 5. Likely, a usercan mount the battery device 10 without having to look at the backsideof the battery device 10 for aid in alignment.

The case 11 of the battery device 10 is preferably formed with a firstwater discharge hole 28 and a second water discharge hole 68 (see FIGS.4 and 7) for discharging water that may enter inside of the case 11.Therefore, the water discharge performance of the case 11 can beimproved. In this example, the positions of the first and second waterdischarge holes 28 and 68 are preferably chosen such that water can beefficiently discharged when the battery device 10 is turned upside down.Thus, in order to discharge water that has entered inside of the case11, the user may turn upside down the battery device 10, for example,from the position shown in FIGS. 5 and 7, so that the water may bedischarged from the first and second water discharge holes 28 and 68 tothe outside of the case 11.

As shown in FIG. 7, the first water discharge hole 28 is preferablyformed in the upper wall of the rear portion of the case 11 tocommunicate with the inside and the outside of the case 11. Morespecifically, the first water discharge hole 28 is preferably positionedon the upper side of the male hook member 52. Therefore, when thebattery device 10 is turned upside down, the first water discharge hole28 is positioned on the lower side of the male hook member 52. Thus,water that happens to enter the inside of the case 11 from the regionwhere the male hook member 52 is provided, can be discharged from thefirst discharge hole 28.

Also, as shown in FIG. 7, the second water discharge hole 68 ispreferably formed in the upper wall of the enclosure portion 60 disposedat the front portion of the case 11. The second water discharge hole 68preferably communicates with the inside and the outside of the case 11.The second water discharge hole 68 is preferably positioned on the upperside of the main control circuit board 62. Therefore, when the batterydevice 10 is turned upside down, the second water discharge hole 68 ispositioned at the lowest position of the enclosure portion 60. Thus,water that may enter inside of the case 11 from the region where themain control circuit board 62 is provided, can be discharged from thesecond discharge hole 68. Therefore, it is possible to prevent waterfrom being stored around the main control circuit board 62.

With the battery device 10 of this example, two battery packs 90 can bemounted to the battery device 10 in a juxtaposed relationship with eachother. In this example, the lengths of the battery packs 90 in theirlongitudinal directions are the same. When the battery packs 90 aremounted to the battery mount sections 20, the longitudinal directions ofthe battery packs 90 extend substantially parallel to each other. Inthis fashion, the length of a group of the battery packs 90 can beminimized their thickness as a group can be minimized. As a result, itis possible to reduce the length and the thickness of the entire batterydevice 10 with the battery packs 90 mounted.

In addition, the main control circuit board 62 may be positioned toextend in a direction intersecting the longitudinal directions of thebattery packs 90. This serves to minimize the size of the battery device10 in a direction along the longitudinal directions of the battery packs90.

Further, the battery pack 90 may be mounted to each of the battery mountsections 20 as the battery pack 90 is slid in the mounting direction.The mounting direction is preferably substantially parallel to thelongitudinal direction of each battery pack 90.

With this arrangement, slide mechanisms 21 for the sliding movement ofthe battery packs 90 may be provided in regions along the longitudinaldirections of the battery packs 90. In this way, it is possible toensure a sufficient length of the slide mechanisms 21 and the guiderails 23. As a result, mounting the battery packs 90 can be performedquickly and easily.

With the battery device 10 of this example, the enclosure portion 60 mayextend on the battery mounting side (where the battery packs 90 aremounted) along a direction intersecting a plane along which the batterymount sections 20 are juxtaposed with each other. Therefore, the spaceoccupied by the enclosure portion 60 can be determined based on theconfiguration and the size of the battery packs 90. Therefore, theconfiguration and the size of the battery device 10 can be minimized tocorrespond to the size and the configuration of the battery packs 90. Inaddition, because the battery mount sections 20 and the enclosureportion 60 are arranged to form an L-shape as viewed from the extendingdirection of the enclosure portion 60, the battery device 10 can beconfigured to surround the battery packs 90 from two different sides(i.e., two different directions). Further, because the main controlcircuit board 62 may be disposed within the enclosure portion 60, thebattery mount sections 20 can be configured to function exclusively forholding the battery packs 90. Therefore, the size of the battery device10 with the battery packs 90 attached thereto can be minimized. It isalso possible to reduce the volume of the battery mount sections 20 thusleading to a reduction in the volume of the battery device 10.

In addition, the thickness (i.e, the size in the vertical direction) ofthe battery mount sections 20 is preferably set to be thinner than thethickness of the battery packs 90 to be mounted to the battery mountsection 20. Therefore, it is possible to reduce the vertical length ofthe battery device 10 when the battery packs 10 are mounted to thebattery mount section 20. In this way, the size of the battery device 10can be minimized. Further, when the battery packs 90 are mounted to thebattery device 10, the finger insertion space having a distance S1 maybe formed between the battery packs 90 and the enclosure portion 60.Therefore, the user can easily removed the battery packs 90 from thebattery mount sections 20 by inserting his or her fingers into thefinger insertion space. Hence, the operations for mounting the batterypacks 90 from the battery mount sections 20 and for removing the batterypacks 90 from the battery mount sections 20 can be easily performed. Inaddition, when the battery packs 90 are mounted to the battery mountsections 20, the upper end surface 601 of the enclosure portion 60exposed outside of the enclosure portion 60 may be positioned atsubstantially the same level as the upper surfaces 901 of the batterypacks 90. In other words, the upper surface 601 and the upper surfaces901 may extend substantially within the same plane. Therefore, byturning the battery device 10 upside down, the battery device 10 can beplaced on a surface with the upper end surface 601 of the enclosureportion 60 and the upper surfaces 901 of the battery packs 90 contactingthe surface. Hence, the battery device 10 with the battery packs 90mounted thereto can be placed in a stable position on such surface.

Embodiments will now be described with reference to FIGS. 8 and 9. Adistance between the juxtaposed battery mount sections 20 in the leftand right directions (widthwise directions) in this example may belarger that that of previous embodiments. Therefore, the battery device10A will be described in connection with the distance between the twojuxtaposed battery mount sections. In addition, in FIGS. 8 and 9, likemembers are given the same reference numerals as previous examples andthe description of these members will not be repeated.

A finger insertion space having a distance S2 may be foinied between thetwo battery packs 90 mounted to the battery mount sections 20.Therefore, the user can insert his or her fingers into the fingerinsertion space, for example, when the user slide-mounts the batterypacks 90 to the battery mount sections 20. For example, the distance S2may be set to be about 10 to 20 mm. Thus, the distance between thebattery mount sections 20 may provide a distance S2 between the twobattery packs 90. Because the user can apply his or her fingers to theleft and right side surfaces of the battery packs 90, the user caneasily grasp the battery packs 90. Therefore, the operations formounting the battery packs 90 to the battery device 10 and for removingthe battery packs 90 from the battery device 10 can be easily performed.

An example will now be described with reference to FIG. 10. A batterydevice 10B according to this example preferably has an enclosure portion70 is disposed between the juxtaposed two battery mount sections 20 inthe left and right directions (widthwise directions). The battery device10B will be described only in connection with the enclosure portion 70.In addition, in FIG. 10, like members are given the same referencenumerals as previous embodiments and the description of these memberswill not be repeated.

As shown in FIG. 10, the two battery packs 90 mounted to the batterymount sections 20 are preferably spaced from each other by a distance S3in the left and right direction (widthwise direction). The enclosureportion 70 is preferably positioned in the space having the distance Sbetween the two battery packs 90. The enclose portion 70 may be formedintegrally with the case 11 and define a space that communicates withinside of the battery mount sections 20 disposed at the lower portion ofthe battery device 10B. It may also communicate with inside of theenclosure portion 60. A control circuit board 72 may be disposed withinthe enclosure portion 70. Therefore, a space for installing the controlcircuit board 72 can be provided in the enclosure portion 70. Thecontrol circuit board 72 may be a different circuit board from the maincontrol circuit board 62.

The above examples may be modified in various ways. For example,although the battery packs 90 have been mounted to the battery mountsections 20 as they are slid onto the battery mount sections 20, it maybe possible to configure such that each battery pack 90 is mounted tothe corresponding battery mount section 20 by using any other suitablemounting structure, such as a fitting structure.

The above examples may be further modified in various ways. For example,for the enclosure portion 60, it is preferable that the enclosureportion 60 extends on the battery mounting side (where the battery packs90 are mounted) along the direction intersecting with a direction of aplane along which the battery mount sections 20 are juxtaposed with eachother. The position and the arrangement of the enclosure portion 60 maybe changed as needed.

Further, according the above example, the mount section 40 for mountingthe battery device 10 to the mount section 5 of the tool body 2 has aslide mechanism 21, so that the battery device 10 can be slide-mountedvia the slide mechanism 21 to the mount position onto the tool body 10.The mount section 40 includes the engaging mechanism 51 for engaging thetool body 2 when the battery device 10 is in the mount position. Theengaging mechanism 51 preferably includes the operation portion 55 usedfor releasing the tool body 2. The operation portion 55 preferablyincludes the pushing force receiving surface 56 that can be pushed foroperating the operation member 55. The pushing force receiving surface56 extends substantially in the mounting direction. Therefore, theengaging mechanism 51 can hold the battery device 10 at the mountposition with respect to the tool body 2 after the battery device 10 hasbeen moved to the mount position. In addition, because the pushing forcereceiving surface 56 extends substantially in the mounting direction,the size of the battery device 10 in the direction perpendicular to themounting direction can be minimized. It can be minimized even with theaddition of the operation portion 55 of the engaging mechanism 51.Therefore, the size of the battery device 10 can be minimized even withthe inclusion of the engaging mechanism 51 for holding the batterydevice 10 at the mount position.

Pushing the pushing force receiving surface 56 may move the male hookportion 53 to move in a direction opposite the protruding direction, sothat the male hook portion 53 may be disengaged from the female hookportion of the tool body 2. Because the pushing force receiving surface56 extends substantially perpendicular to the protruding direction ofthe male hook portion 53, the pushing force may be applied in the samedirection as the moving direction of the male hook portion 53.Therefore, the operation for releasing engagement of the male hookportion 53 can be performed easily and efficiently.

In addition, the pushing force receiving surface 56 preferably has alength in the mounting direction (i.e., the sliding direction or theforward and rearward directions) of the battery device 10. It preferablyhas a width (in the left and right direction) in a directionperpendicular to the mounting direction. Because the length is set to belonger than the width, the pushing operation on the pushing forcereceiving surface for releasing the male hook portion can befacilitated.

Further, the marker 65 is preferably disposed on the upper side oppositeto the backside of the battery device 10 where the mount section 40 formounting to the tool body 2 is disposed. The marker 69 serves as atarget for movement of the mount section 40 relative to the tool body 2when the mount section 40 is mounted to the tool body 2. Therefore, theuser can smoothly attach the mount section 40 to the tool body 2 as heor she views the marker 69. Therefore, the operation for mounting thebattery device 10 to the tool body 1 can be easily performed withouthaving to look at the region between the battery device 10 and the toolbody 2.

The marker 65 preferably includes two marker lines defined by theopposite end edges 651 and 652 of the marker 65. The battery device 10can be mounted to the tool body 2 by moving the battery device 10towards the marker lines. In this way, mounting the mount section 40 tothe tool body 2 can be further easily performed. The end edges 651 and652 serving as the marker lines are preferably spaced from each other bya distance corresponding to a width of the battery pack 90 or anotherbattery pack having a rating voltage of 36 V. The tool body 2 preferablyhas markers 5 a and 5 b spaced from each other by a distancecorresponding to the width of the battery pack 90 or another batterypack described above. Therefore, the markers 5 a and 5 b of the toolbody 2 may be used when mounting the battery device 10 to the tool body2 and may be also used when a single battery pack is directly mounted tothe tool body 2.

In previous embodiments, a main control circuit board 62 transforms theoutput voltage of the 18 V from the battery packs 90 into a voltage of36 V that is supplied to the mower body 2. In a similar fashion, othercontrol circuit boards, such as a control circuit board for controllinga displaced device associated with the battery device 10, may bepositioned within the enclosure portion 60. Thus, in addition to themain control circuit board 62, the battery device 10 may include anauxiliary control circuit board(s) for performing any other controlrelated to the battery device 10.

Furthermore, the upper end surface 601 of the enclosure portion 60 andthe upper surfaces 901 of the battery packs 90 mounted to the batterymount sections 20 have been described. The surface of the enclosureportion 60 and the surfaces of the battery packs 90 may extendsubstantially within the same plane. The left side surface 602 mayextend within substantially the same plane as the left side surface 902of the left side battery pack 90. Similarly, the right side surface 602may extend within substantially the same plane as the right side surface902 of the right side battery pack 90. With this arrangement, it is alsopossible to place the battery device 10 on a surface in a stable manner.

Furthermore, although the above examples have been described inconnection with the lawn mower 1, the above teachings can also beapplied to other battery driven electric tools, such as battery drivenchain saws.

What is claimed is:
 1. A battery carrier configured to be mounted to atool body of an electric tool for supplying electric power to the toolbody, comprising: a plurality of battery mount sections disposed at afirst surface of the battery carrier and each configured to hold abattery; a tool body mount section disposed at a second surface of thebattery carrier opposite to the first surface and configured to bemounted to the tool body; a marker disposed at the first surface andserving as a target for movement of the tool body mount section relativeto the tool body when the tool body mount section is mounted to the toolbody; the tool body mount section including a first slide mechanismconfigured to slide in a first sliding direction along the tool body;and a first case portion including the plurality of battery mountsections and the tool body mount section; a second case portionextending from the first case portion in a direction away from the firstsurface; and the marker protruding from an end surface of the secondcase portion and having opposite ends in a direction perpendicular tothe sliding direction, the opposite ends defining marker lines; and themarker lines extending parallel to the first sliding direction.
 2. Thebattery carrier according to claim 1, wherein the first surface includesa front portion and a rear portion with respect to the first slidingdirection, and the marker is disposed at the front portion of the firstsurface.
 3. The battery carrier according to claim 2, wherein the markeris positioned on a front side of the batteries with respect to the firstsliding direction when the batteries are mounted to the plurality ofbattery mount sections.
 4. The battery carrier according to claim 3,wherein each of the plurality of battery mount sections includes asecond slide mechanism configured such that the battery is slid in asecond sliding direction along the first surface, and the second slidingdirection is parallel to the first sliding direction.
 5. The batterycarrier according to claim 3, wherein: the second case portion forms anenclosure portion disposed at the front portion of the first surface ofthe battery carrier and protruding from the first surface; the enclosureportion is positioned on the front side of the batteries with respect tothe first sliding direction when the batteries are mounted to theplurality of battery mount sections; and the marker is disposed at theenclosure portion.
 6. The battery carrier according to claim 5, whereinthe enclosure portion includes a first end and a second end in adirection perpendicular to the first surface, the first end beingpositioned on a side of the first surface and the second end beingopposite to the first end, and the marker is disposed at the second endof the enclosure portion.
 7. The battery carrier according to claim 1,wherein the end surface includes a first edge and a second edge oppositeto each other in a direction substantially perpendicular to the firstsliding surface, and the marker is defined by the first and secondedges.
 8. The battery carrier according to claim 5, wherein theenclosure portion has a longitudinal length in a direction substantiallyperpendicular to the first sliding direction.
 9. The battery carrieraccording to claim 5, wherein the enclosure portion defines an internalspace that accommodates a control circuit board, and the control circuitboard is configured to control an output voltage of the batteries. 10.The battery carrier according to claim 1, wherein the marker linesextend parallel to each other.
 11. The battery carrier according toclaim 10, wherein the marker lines include a first maker line and asecond marker line displaced from each other by a distance correspondingto a width of one battery.
 12. The battery carrier according to claim 1,wherein a tool-side marker is disposed at the tool body to correspond tothe marker line of the battery carrier, and the marker line of thebattery carrier is arranged such that the tool-side marker is alignedwith the marker line in the first sliding direction when the batterycarrier is mounted to the tool body.
 13. The battery carrier accordingto claim 1, wherein the plurality of battery mount sections are arrangedin a juxtaposed relationship along the first surface.
 14. The batterycarrier according to claim 1, wherein the first case portion and thesecond case portion of the case jointly form a substantially L-shape asviewed from a side view.